• Try this instead

    missed a few , and " out

    =SWITCH

    (

    LAST(Fields!Value.Value, "DataSet1") = 0, "White",

    FIRST(Fields!Value.Value, "DataSet1") >= LAST(Fields!Value.Value, "DataSet1"), "Green",

    (FIRST(Fields!Value.Value, "DataSet1") / LAST(Fields!Value.Value, "DataSet1")) >= 0.7, "Yellow",

    (FIRST(Fields!Value.Value, "DataSet1") / LAST(Fields!Value.Value, "DataSet1")) < 0.7, "Red"

    )